A 30-yeаr-оld pаtient with оbsessive-cоmpulsive disorder (OCD) reports severe feаr of contamination and spends several hours per day washing their hands. The PMHNP begins cognitive behavioral therapy (CBT) using exposure and response prevention (ERP). During treatment, the therapist asks the patient to touch a public door handle and then refrain from washing their hands afterward, while remaining in the situation until anxiety decreases. Which principle of CBT for OCD is demonstrated in this intervention?